How to Repair Sink Leaks
- 1). Place a bucket under the sink below the drain pipe and turn on the faucet to run water. Shine a flashlight beneath the sink and around the drain pipe to locate the leak. Turn off the water.
- 2). Unscrew the large hex nut attached to the underside of the sink and the hex nut connected to the pipe below where the pipe attaches to the curved P-trap. Catch the water in the bucket under the sink and turn the P-trap upside down over the bucket to empty the pipe of water.
- 3). Tap the pipe hanging below the sink with a rubber mallet to dislodge the pipe and flange. Push upward to remove the flange and pipe from the inside of the sink.
- 4). Clean the hole in the bottom of the sink with a rag to remove grime and slime.
- 5). Roll out a rope of plumber's putty to form a circle large enough in diameter to fit around the hole inside your sink. Place the ring of putty over the hole.
- 6). Set the round rubber gasket that comes with your new flange onto the circle of plumber's putty. Insert the drain pipe and flange into the sink and through the rubber gasket so the pipe extends below the sink. Press the flange to seat it on the gasket and squeeze the putty to form a tight seal.
- 7). Wrap plumber's tape around the threaded ends of the drain pipe and the P-trap. The white tape helps seal the pipe joints.
- 8). Slide a hex nut over the drain pipe and onto the threads under the flange where it hangs below the sink. Turn the hex nut to the right with a wrench to tighten it securely to the sink. Tightening also places pressure on the rubber gasket and plumber's putty to form a watertight barrier.
- 9). Attach the new P-trap to the drain pipe and the wall pipe with hex nuts and the wrench.
- 10
Turn on the faucet to run water down the drain so you can check your work for leaks.
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